Java & OS X Integration
Apple provides an Application class that allows you to integrate your application with the OS X environment. It allows Java applications to behave more like native OS X applications.
Handling Quit
Following snippet will install an window listener and run your clean up code before the application is exited. However when user selects Quit instead of hitting the red dot clean up code will not run.
addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent we){
//do something here
System.exit(0);
}});
In order to handle quit menu item. Apple's Application class class provides handlers. But as a down side these classes are apple only classes you should not load them when you are not OS X. So wrap them in a class and load that class only when you are on OS X and use standard window listener on other operating systems.
import com.apple.eawt.*;
import com.apple.mrj.*;
public class MacApplication extends Application {
public MacApplication( ) {
public void handleQuit( ApplicationEvent event ) {
// do something here...
System.exit(0);
}
});
}
}
Now when Quit menu item is selected your application will run your clean up code.
Hiding your application
When you close a window on a mac, application is kept running and only the window is hidden. In order for our application to play nice with native applications we should also implement this. Fortunately Application class provides a handler for that too.
public void handleReOpenApplication(ApplicationEvent event) {
//mainFrame.setVisible(true);
}
Now when the dock icon is clicked your application will be visible and when the red dot is clicked, it will only be hidden. Don't forget to set your main frame's default close operation to hide.
Knowing your OS
If you are not on OS X, you shouldn't load MacApplication class. On mac's mrj.version system property is always set you can check it's value to see if you are on a mac. If it's set create your application object.
if(System.getProperty("mrj.version") == null){
addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent we){
//not on a mac cleanup
System.exit(0);
}});
}else{
MacApplication macApplication = new MacApplication( );
}